Opening/Closing Device and Mobile Device Using the Same

Abstract

It is an object of the present invention to provide an opening/closing device which can be produced simple in construction and reduce the surface pressure of its cam portions, and a mobile phone which can be reduced in cost and sufficiently reliable in the hinged members by using the opening/closing device. In the opening/closing device operable to rotate the second member ( 30 ) with respect to the first member ( 20 ) hingedly connected the second member ( 30 ) in an opening operation direction by operating first and second rotation cams ( 160, 140 ), and a movable cam ( 150 ) held in engagement with the second rotation cam ( 140 ) in response to the displacement of the operation cam ( 130 ), the second rotation cam ( 140 ) and the movable cam ( 150 ) have a plurality of kinds of end cam portions (( 142, 153 ), ( 143, 154 )) formed thereon at different radiuses (r 1, r 2 ) from the guide center axis ( 110 c ) in opposing relationship with each other, the urging direction of the urging means ( 170 ) to the second member ( 30 ) is changed by the end cam portions (( 142, 153 ), ( 143, 154 )) when the operation cam ( 130 ) is operated to cause the first rotation cam ( 160 ) to be rotated from the predetermined operation starting position.

1 . A hinge device comprising:
 a fixed guide member ( 110 ) fixed to a first member ( 20 ) to be hingedly connected and having a guide center axis ( 10   a ) extending along a center axis of a hinge connection;   an operation cam ( 130 ) supported on said fixed guide member to be displaceable with respect to said fixed guide member in a predetermined operation direction by an external operation force;   a first rotation cam ( 160 ) rotatably supported on said fixed guide member to be engaged with said operation cam and to be rotated with respect to said fixed guide member around said guide center axis in response to the displacement of said operation cam;   a second rotation cam ( 140 ;  240 ;  340 ) supported on said fixed guide member to be displaceable along and rotatable around said guide cent axis in response to the rotation of said first rotation cam;   a movable cam ( 150 ;  250 ;  350 ) regulated from being rotated around said guide center axis with respect to a second member ( 30 ) hingedly connected with said first member, and positioned in face-to-face relationship with said second rotation cam and displaceable with respect to said fixed guide member along said guide center axis and rotatable around said guide center axis;   urging means ( 170 ) for urging said movable cam toward said second rotation cam in one of an opening operation direction ( 10   e ) to have said second member moved away from said first member and a closing operation direction ( 10   d ) to have said second member moved toward said first member in response to the engagement state of said second rotation cam and said movable cam, and   returning means ( 190 ) for returning said first rotation cam to a predetermined operation starting position of said operation cam and for returning said second rotation cam to a predetermined operation starting position where said second member is urged toward said closing operation direction by said urging means,   said second member being rotated with respect to said first member toward said opening operation direction through said movable cam by the urging force of said urging means when said operation cam is displaced in said predetermined operation direction by said external operation force, wherein   said second rotation cam and said movable cam respectively have a plurality of kinds of end cam portions (( 142 ,  153 ), ( 143 ,  154 ); ( 242 ,  253 ), ( 243 ,  254 ); ( 342 ,  353 ), ( 343 ,  354 )) formed thereon at different radiuses from said guide center axis in opposing relationship with each other, said plurality of kinds of end cam portions including urging direction changing outer cam portions (( 142 ,  153 ); ( 242 ,  253 ); ( 342 ,  353 )) changed in engagement state while being axially pressed by said urging means to allow the urging direction of said second member to be changed when said operation cam is operated to cause the first rotation cam to be rotated from the predetermined operation starting position, and urging direction changing inner cam portions (( 143 ,  154 ); ( 243 ,  254 ); ( 343 ,  354 )) engaged with each other at respective positions closer to said guide center axis than said urging direction changing outer cam portions and changed in engagement state in synchronism with said urging direction changing outer cam portions while being axially pressed by said urging means to allow the urging direction of said second member to be changed when said operation cam is operated to cause the first rotation cam to be rotated from the predetermined operation starting position.   
     
     
         2 . A hinge device as set forth in  claim 1 , in which said urging direction changing outer cam portion ( 142 ;  242 ;  342 ) and said urging direction changing inner cam portion ( 143 ;  243 ;  343 ) of said second rotation cam are positioned in opposing relationship with each other across said rotation center axis of said second rotation cam and 180 degrees spaced apart from each other in the rotation direction of said second rotation cam. 
     
     
         3 . A hinge device as set forth in  claim 1 , in which said urging direction changing outer cam portion ( 142 ;  242 ;  342 ) and said urging direction changing inner cam portion ( 143 ;  243 ;  343 ) of said second rotation cam respectively have first inclined cam surfaces (( 142   a;    242   a;    342   a ) or ( 143   a;    243   a;    343   a )) inclined in predetermined directions with respect to a surface perpendicular to said guide center axis to urge said movable cam toward the closing operation direction of said second member when said second member is positioned in the neighborhood of the closing operation position closest with said first member in the state of said second rotation cam returned to the predetermined operation starting position, and second inclined cam surfaces ((( 142   c,    142   d,    142   e ); ( 242   c,    242   d,    242   e ); ( 342   c,    342   d,    342   e )) or (( 143   c,    143   d,    143   e ); ( 243   c,    243   d,    243   e ); ( 343   c,    343   d,    343   e ))) inclined with respect to said surface perpendicular to said guide center axis, and top portions (( 142   b;    242   b;    342   b ) or ( 143   b;    243   b;    343   b )) projected toward said movable cam between said first inclined cam surfaces and said second inclined cam surfaces to allow said urging direction of said second member to be changed by said urging means. 
     
     
         4 . An opening/closing device as set forth in  claim 1 , in which said fixed guide member has guide shaft portions ( 116 ,  180 ) in coaxial relationship thereof, said first rotation cam and said second rotation cam being guided by said guide shaft portion ( 116 ) in coaxial relationship with said fixed guide member. 
     
     
         5 . A hinge device as set forth in  claim 5 , further comprising a bottomed cylindrical body ( 120 ) supported on and coaxial with said guide shaft portion and integrally engaged in rotation direction with said movable cam and said second member, said urging means being constituted by a resilient member ( 170 ) positioned between said bottomed cylindrical body and said movable cam. 
     
     
         6 . A hinge device as set forth in  claim 1 , in which said fixed guide member and said movable cam have respective end surface positioning cam portions ( 116   a,    151   a ) axially opposing with each other, said movable cam being disengaged from said second rotation cam to have said end surface positioning cam portions of said fixed guide member and said movable cam engaged with each other and to have said second member positioned and retained at the opening position when said second member is moved to the opening position where said second member is remotest from said first member. 
     
     
         7 . A hinge device as set forth in  claim 6 , in which said end surface positioning cam portions of said fixed guide member and said movable cam are engaged with and disengaged from each other at a radius position closer to said guide center axis than said kinds of end cam portions. 
     
     
         8 . A hinge device as set forth in  claim 3 , in which said second inclined cam surface (( 142   c,    142   d,    142   e ) or ( 143   c,    143   d,    143   e )) of said urging direction changing outer cam portion ( 142 ) and said urging direction changing inner cam portion ( 143 ) of said second rotation cam has side portions (( 142   c,    142   e ) or ( 143   c,    143   e )) inclined at different grades with respect to the surface perpendicular to said guide center axis and an intermediate portion ( 142   d  or  143   d ) intervening between said side portions, said intermediate portion rotate said second member at a reduced speed when said second member is rotated with respect to said first member in said opening operation direction. 
     
     
         9 . A hinge device as set forth in  claim 3 , in which said second inclined cam surface (( 342   c,    342   d,    342   e ) or ( 343   c,    343   d,    343   e )) of said urging direction changing outer cam portion ( 342 ) and said urging direction changing inner cam portion ( 343 ) of said second rotation cam has side portions (( 142   c,    142   e ) or ( 143   c,    143   e )) and an intermediate portion ( 142   d  or  143   d ) intervening between said side portions, and being inclined oppositely to and said side portions each other at different grades with respect to the surface perpendicular to said guide center axis to allow said intermediate portions of said second inclined cam surfaces to stop said second member when said second member is rotated by the urging force of said urging means with respect to said first member in said opening operation direction. 
     
     
         10 . A mobile device using said opening/closing device as set forth in  claim 1 , said first member  20  and said second member  30  hingedly connected with each other collectively constitute an openable and closable housing of a foldable type.